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Environmental Matters - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2022 USD ($)
Environmental Restoration Costs
Site Contingency [Line Items]
Estimated Costs Accrued For Remediation	$ 0.8
Maine | Environmental Restoration Costs
Site Contingency [Line Items]
Amortization period for environmental costs	5 years
New Hampshire
Site Contingency [Line Items]
Amortization period for environmental costs	7 years

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- Definition

The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

+ References

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